SURFACE-COATING CUTTING TOOL HAVING HARD COATING LAYER EXERTING EXCELLENT ABRASION RESISTANCE AND PEELING RESISTANCE

• Main Authors: MURAKAMI AKIHIRO, OKUDE MASAKI, HONMA HISASHI
• Format: Patent
• Language: English; Japanese
• Published: 10.09.2020
• Subjects: BORING; CHEMICAL SURFACE TREATMENT; CHEMISTRY; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATIONOR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY IONIMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; COATING MATERIAL WITH METALLIC MATERIAL; COATING METALLIC MATERIAL; DIFFUSION TREATMENT OF METALLIC MATERIAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION INGENERAL; MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR; METALLURGY; PERFORMING OPERATIONS; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THESURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; TRANSPORTING; TURNING

To provide a surface-coating cutting tool that exerts excellent abrasion resistance and peeling resistance.SOLUTION: In the surface-coating cutting tool, a hard coating layer having a lower layer and an upper layer is formed at a surface side of a base body of the tool. The lower layer has a Ti compound layer having total average layer thicknesses of 0.1-3.0 μm. The upper layer has a cubic crystal Ti1-xTaxN1-yCy (0.30≤x≤0.90, 0<y≤0.60) layer having an average layer thickness of 1.0-15.0 μm and has a composition variable structure with a columnar construction having an average grain width of 2-100 nm in which Ta content ratios and C content ratios vary periodically in a direction at 0-10° with respect to a normal line of the base body of the tool, where an average interval between maximum content points and minimum content points adjacent thereto which are repeated are 2-20 nm in the Ta quantities and C quantities, an average value of absolute values of differences Δx and Δy between the maximum content ratio and the minimum content ratio of the Ta and C in respective points is 0.04 or more, and a distance between the Ta maximum content point and the C maximum content point closest thereto is equal to one fifths of the average interval of the Ta quantities.SELECTED DRAWING: Figure 1 【課題】すぐれた耐摩耗性および耐剥離性を発揮する表面被覆切削工具の提供。【解決手段】工具基体の表面側に下部層と上部層を有する硬質被覆層が形成され、前記下部層は、合計平均層厚０．１〜３．０μｍのＴｉ化合物層を有し、前記上部層は、平均層厚１．０〜１５．０μｍの立方晶Ｔｉ１−ｘＴａｘＮ１−ｙＣｙ（０．３０≦ｘ≦０．９０、０＜ｙ≦０．６０）層を有し、工具基体の法線に対し０〜１０°の方向にＴａ含有割合およびＣ含有割合が周期的に変化する、平均粒子幅が２〜１００ｎｍの柱状構造の組成変動組織を有し、Ｔａ量およびＣ量について、繰り返す最高含有点とそれぞれ隣接する最低含有点の平均間隔は２〜２０ｎｍであり、前記それぞれの位置におけるＴａおよびＣの最高含有割合と最低含有割合の差ΔｘおよびΔｙの絶対値の平均値が０．０４以上であり、Ｔａ最高含有点と最も近いＣ最高含有点との距離が、前記Ｔａ量の平均間隔の１／５以下である表面被覆切削工具。【選択図】図１